Brute-Force Crack - Computer Definition

A trial-and-error, exhaustive effort used by
application ­programs to decrypt encrypted data such as passwords or reveal Data Encryption Standard (DES) keys. Just as criminals try
breaking into safes by trying multitudes of possible number combinations, a
brute-force crack is considered by experts to be an infallible but time-­consuming
activity. Another form of brute-forcing is that used against an authentication
mechanism. This form tries to break into the authentication mechanism by
brute-forcing all possible passwords within a range set forth by the attacker.

More “intelligent” approaches limit the search space by
using likely passwords derived
from words in dictionaries and name lists first and then generate fully
enumerated lists only if these initial attempts fail. These are called
dictionary attacks. The success rate for dictionary-based cyber attacks is
embarrassingly high.